钴氮共掺杂TiO_2的制备及其光催化活性

以钛酸四丁酯为原料,采用沉淀-浸渍法制备了N和Co共掺杂纳米光催化剂Co/N/TiO_2。采用紫外-可见漫反射、X射线衍射和透射电子显微镜等技术对催化剂的吸光性能、结晶形态和粒径进行了表征。以活性艳蓝X-BR溶液为光降解模型,评价了Co/N/TiO_2的可见光催化活性,并与AEROXIDE TiO_2 P25的性能进行了对比。实验结果表明,在n(Co):n(N):n(Ti)=0.16:0.2:1、煅烧温度400℃、煅烧时间2.5 h的最优条件下制备的Co/N/TiO_2为单一的锐钛矿相,平均粒径为11.1 nm,比表面积为140.77 m~2/g;且Co/N/TiO_2的吸收边红移现象显著,吸收可见光的性能强,具有良好的可见光催化活性,在纯粹可见光(波长大于400 nm)下对活性艳蓝X-BR溶液的降解率达到87.50%。

Preparation of TiO_2 Co-Doped with Cobalt and Nitrogen and Its Photocatalytic Activity

Using tetrabutyl titanate as starting material, Co/N/TiO_2 co-doped nano photocatalyst was prepared by precipitation-doping method. The optical behavior, crystalline phase,morphology and particle size of the prepared photocatalyst were characterized by means of UV-visible DRS,XRD and TEM. The photocatalytic activity of Co/N/TiO_2 was evaluated by photodegradation of reactive brilliant blue X-BR as probe reaction and compared with activity of AEROXIDE TiO_2 P25. The experiments showed that Co/N/TiO_2 was in sole anatase phase. The optimum preparation conditions were: n(Co) ∶ n(N) ∶ n(Ti) 0.16 ∶ 0.2 ∶ 1, calcination temperature 400 ℃ for 2.5 h. Average particle diameter and specific surface area of the obtained Co/N/TiO_2 were 11.1 nm and 140.77 m~2/g respectively. Absorption edge of Co/N/TiO_2 shifted significantly, its absorption performance under visible light was prominent, and so was its photocatalytic activity. Photodegradation rate of reactive brilliant blue X-BR on the photocatalyst under visible light(λ＞400 nm) reached 87.50%.